Cyclophosphamide in the treatment of toxic epidermal necrolysis

Stevens-Johnson syndrome and toxic epidermal necrolysis: A systematic review of PubMed/MEDLINE case reports from 1980 to 2020

Background

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare, life-threatening immunologic reactions. Prior studies using electronic health records, registries or reporting databases are often limited in sample size or lack clinical details. We reviewed diverse detailed case reports published over four decades.

Methods

Stevens-Johnson syndrome and toxic epidermal necrolysis-related case reports were identified from the MEDLINE database between 1980 and 2020. Each report was classified by severity (i.e., SJS, TEN, or SJS-TEN overlap) after being considered a “probable” or “definite” SJS/TEN case. The demographics, preconditions, culprit agents, clinical course, and mortality of the cases were analyzed across the disease severity.

Results

Among 1,059 “probable” or “definite” cases, there were 381 (36.0%) SJS, 602 (56.8%) TEN, and 76 (7.2%) SJS-TEN overlap cases, with a mortality rate of 6.3%, 24.4%, and 21.1%, respectively. Over one-third of cases had immunocompromised conditions preceding onset, including cancer (n = 194,18.3%), autoimmune diseases (n = 97, 9.2%), and human immunodeficiency virus (HIV) (n = 52, 4.9%). During the acute phase of the reaction, 843 (79.5%) cases reported mucous membrane involvement and 210 (19.8%) involved visceral organs. Most cases were drug-induced (n = 957, 90.3%). A total of 379 drug culprits were reported; the most frequently reported drug were antibiotics (n = 285, 26.9%), followed by anticonvulsants (n = 196, 18.5%), analgesics/anesthetics (n = 126, 11.9%), and antineoplastics (n = 120, 11.3%). 127 (12.0%) cases reported non-drug culprits, including infections (n = 68, 6.4%), of which 44 were associated with a mycoplasma pneumoniae infection and radiotherapy (n = 27, 2.5%).

Conclusion

An expansive list of potential causative agents were identified from a large set of literature-reported SJS/TEN cases, which warrant future investigation to understand risk factors and clinical manifestations of SJS/TEN in different populations.

Severe Cutaneous Adverse Drug Reactions: Presentation, Risk Factors, and Management

PURPOSE OF STUDY

Immune-mediated adverse drug reactions occur commonly in clinical practice and include mild, self-limited cutaneous eruptions, IgE-mediated hypersensitivity, and severe cutaneous adverse drug reactions (SCAR). SCARs represent an uncommon but potentially life-threatening form of delayed T cell-mediated reaction. The spectrum of illness ranges from acute generalized exanthematous pustulosis (AGEP) to drug reaction with eosinophilia with systemic symptoms (DRESS), to the most severe form of illness, Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN).

RECENT FINDINGS

There is emerging literature on the efficacy of cyclosporine in decreasing mortality in SJS/TEN. The purpose of our review is to discuss the typical presentations of these conditions, with a special focus on identifying the culprit medication. We review risk factors for developing SCAR, including HLA alleles strongly associated with drug hypersensitivity. We conclude by discussing current strategies for the management of these conditions.

Chronic Ocular Complications of Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis: The Role of Systemic Immunomodulatory Therapy

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare, but potentially blinding diseases that affect the skin and mucous membranes. Although the cutaneous manifestations tend to be self-limited and resolve without sequelae, the chronic ocular complications associated with SJS/TEN can persist despite local therapy. Poor understanding of the underlying pathophysiology and lack of a standardized clinical approach have resulted in a paucity of data in regards to suitable treatment options. Inflammatory cellular infiltration and elevated levels of ocular surface cytokines in the conjunctival specimens of affected patients give credence to an underlying immunogenic etiology. Furthermore, the presence of ongoing ocular surface inflammation and progressive conjunctival fibrosis in the absence of exogenous aggravating factors suggest a possible role for systemic immunomodulatory therapy (IMT). We review in detail the proposed immunogenesis underlying chronic ocular SJS/TEN and the possible utility of systemic IMT.

Continuous venovenous hemofiltration combined with hemoperfusion for toxic epidermal necrolysis: a retrospective cohort study

AIM

The current treatments of toxic epidermal necrolysis (TEN) are limited to the discontinuation of a suspect medication and supportive measures. We conducted a retrospective study to evaluate the efficacy of adding continuous venovenous hemofiltration (CVVH) and hemoperfusion (HP) to the conventional treatment for TEN.

METHODS

TEN patients who were admitted to our center between January 2008 and May 2016 were considered as candidates. The included patients were divided into the CVVH&HP group (n = 34) and the conventional group (n = 34) according to their accepted therapies during hospital stay.

RESULTS

The patients in the conventional group had a significantly reduced 28-day survival proportion compared with patients in the CVVH&HP group (73.5 versus 91.2%, p = .047). The adjusted results demonstrated that the conventional group had a significantly higher risk of 28-day mortality as well. Moreover, patients in the CVVH&HP group were associated with significantly shorter hospital stay, rash, fever, and antibiotic durations. However, the addition of CVVH&HP to conventional treatment did not significantly increase the in-hospital cost.

CONCLUSIONS

In conclusion, CVVH&HP might be a safe and effective adjuvant therapy for TEN. Further well-designed studies are warranted to obtain robust evidence.

Phenytoin-induced toxic epidermal necrolysis: Review and recommendations

Toxic epidermal necrolysis (TEN) is a serious, life-threatening skin reaction characterized by severe exfoliation and destruction of the epidermis of the skin. In most TEN cases, drugs are believed to be the causative agent; antipsychotics, antiepileptics, and other medications such as sulfonamides are among the most common causes of drug-induced TEN. Phenytoin, a commonly prescribed medication for seizure, was found to cause TEN. Evidence-based treatment guidelines are lacking, so the best strategy is to identify and avoid potential risk factors and to provide intensive supportive care. The aim of this literature review is to focus on phenytoin-induced TEN, to explore the risk factors, and to highlight the possible treatment options once phenytoin-induced TEN is confirmed.

Cyclophosphamide in dermatology

Cyclophosphamide is a chemotherapeutic agent which was first discovered in experimental tumours in rats, and it has since been widely used to treat malignancies and severe manifestations of various auto-immune diseases. High-dose chemotherapy and continuous daily oral regimens are associated with significant toxicity profiles, but i.v. pulsed regimens have lowered the rates of adverse effects in rheumatological studies. Cyclophosphamide has been shown to be useful in the treatment of severe autoimmune conditions due to its powerful immunosuppressive ability; however, it remains a relatively underused modality in dermatology. This article reviews the current literature on cyclophosphamide and its clinical applications in dermatology.

Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis--A Comprehensive Review and Guide to Therapy. I. Systemic Disease

The intent of this review is to comprehensively appraise the state of the art with regard to Stevens Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN), with particular attention to the ocular surface complications and their management. SJS and TEN represent two ends of a spectrum of immune-mediated, dermatobullous disease, characterized in the acute phase by a febrile illness followed by skin and mucous membrane necrosis and detachment. The widespread keratinocyte death seen in SJS/TEN is rapid and irreversible, and even with early and aggressive intervention, morbidity is severe and mortality not uncommon. We have divided this review into two parts. Part I summarizes the epidemiology and immunopathogenesis of SJS/TEN and discusses systemic therapy and its possible benefits. We hope this review will help the ophthalmologist better understand the mechanisms of disease in SJS/TEN and enhance their care of patients with this complex and often debilitating disease. Part II (April 2016 issue) will focus on ophthalmic manifestations.

Erythema multiforme, Stevens Johnson syndrome, and toxic epidermal necrolysis syndrome in patients undergoing radiation therapy: a literature review

OBJECTIVE

Erythema multiforme (EM), Stevens Johnson syndrome (SJS), and toxic epidermal necrolysis syndrome (TENS) are exfoliative disorders that may present as complications in some patients undergoing radiotherapy. The purpose of this literature review was to determine the reported frequency of these exanthemata in irradiated patients.

METHODS

A comprehensive search from 1903 to 2011, identified 89 articles with 165 cases.

RESULTS

Of 151 evaluable cases, 57 (38%) described EM; 46 (30.5%) SJS; 14 (9%) SJS/TENS overlap; and 34 (22.5%) TENS. Ninety-three percent underwent radiotherapy for either a primary or metastatic malignancy. A majority of patients were simultaneously treated with medications known to precipitate these exanthemata. Of the 61 patients receiving antiepileptic medications during radiotherapy, 48 were treated prophylactically and 13 for seizures, most frequently with phenytoin or phenobarbital. Amifostine was the second most common medication associated with radiotherapy and these reactions. Fourteen (23%) patients on anticonvulsant medication, and 11 (38%) on other medications died compared with 3 (8%) patients treated with radiotherapy alone (P = 0.002). No deaths occurred among irradiated patients receiving amifostine.

CONCLUSIONS

EM, SJS, and TENS were rarely reported in patients undergoing radiotherapy alone. The majority of SJS and TENS occurred in irradiated patients with concomitant prescribed medications.

Cytotoxic proteins and therapeutic targets in severe cutaneous adverse reactions

Severe cutaneous adverse reactions (SCARs), such as Stevens-Johnson syndrome (SJS) and toxic epidermal necrosis (TEN), are rare but life-threatening conditions induced mainly by a variety of drugs. Until now, an effective treatment for SJS/TEN still remains unavailable. Current studies have suggested that the pathobiology of drug-mediated SJS and TEN involves major histocompatibility class (MHC) I-restricted activation of cytotoxic T lymphocytes (CTLs) response. This CTLs response requires several cytotoxic signals or mediators, including granulysin, perforin/granzyme B, and Fas/Fas ligand, to trigger extensive keratinocyte death. In this article, we will discuss the cytotoxic mechanisms of severe cutaneous adverse reactions and their potential applications on therapeutics for this disease.

Toxic epidermal necrolysis and Stevens-Johnson syndrome: a review

OBJECTIVES

The aims of this review are to summarize the definitions, causes, and clinical course as well as the current understanding of the genetic background, mechanism of disease, and therapy of toxic epidermal necrolysis and Stevens-Johnson syndrome.

DATA SOURCES

PubMed was searched using the terms toxic epidermal necrolysis, Stevens-Johnson syndrome, drug toxicity, drug interaction, and skin diseases.

DATA SYNTHESIS

Toxic epidermal necrolysis and Stevens-Johnson syndrome are acute inflammatory skin reactions. The onset is usually triggered by infections of the upper respiratory tract or by preceding medication, among which nonsteroidal anti-inflammatory agents, antibiotics, and anticonvulsants are the most common triggers. Initially the diseases present with unspecific symptoms, followed by more or less extensive blistering and shedding of the skin. Complete death of the epidermis leads to sloughing similar to that seen in large burns. Toxic epidermal necrolysis is the most severe form of drug-induced skin reaction and includes denudation of >30% of total body surface area. Stevens-Johnson syndrome affects <10%, whereas involvement of 10%-30% of body surface area is called Stevens-Johnson syndrome/toxic epidermal necrolysis overlap. Besides the skin, mucous membranes such as oral, genital, anal, nasal, and conjunctival mucosa are frequently involved in toxic epidermal necrolysis and Stevens-Johnson syndrome. Toxic epidermal necrolysis is associated with a significant mortality of 30%-50% and long-term sequelae. Treatment includes early admission to a burn unit, where treatment with precise fluid, electrolyte, protein, and energy supplementation, moderate mechanical ventilation, and expert wound care can be provided. Specific treatment with immunosuppressive drugs or immunoglobulins did not show an improved outcome in most studies and remains controversial. The mechanism of disease is not completely understood, but immunologic mechanisms, cytotoxic reactions, and delayed hypersensitivity seem to be involved.

CONCLUSION

Profound knowledge of exfoliative skin diseases is needed to improve therapy and outcome of these life-threatening illnesses.

Toxic epidermal necrolysis and Stevens-Johnson syndrome

Toxic epidermal necrolysis (TEN) and Stevens Johnson Syndrome (SJS) are severe adverse cutaneous drug reactions that predominantly involve the skin and mucous membranes. Both are rare, with TEN and SJS affecting approximately 1or 2/1,000,000 annually, and are considered medical emergencies as they are potentially fatal. They are characterized by mucocutaneous tenderness and typically hemorrhagic erosions, erythema and more or less severe epidermal detachment presenting as blisters and areas of denuded skin. Currently, TEN and SJS are considered to be two ends of a spectrum of severe epidermolytic adverse cutaneous drug reactions, differing only by their extent of skin detachment. Drugs are assumed or identified as the main cause of SJS/TEN in most cases, but Mycoplasma pneumoniae and Herpes simplex virus infections are well documented causes alongside rare cases in which the aetiology remains unknown. Several drugs are at "high" risk of inducing TEN/SJS including: Allopurinol, Trimethoprim-sulfamethoxazole and other sulfonamide-antibiotics, aminopenicillins, cephalosporins, quinolones, carbamazepine, phenytoin, phenobarbital and NSAID's of the oxicam-type. Genetic susceptibility to SJS and TEN is likely as exemplified by the strong association observed in Han Chinese between a genetic marker, the human leukocyte antigen HLA-B*1502, and SJS induced by carbamazepine. Diagnosis relies mainly on clinical signs together with the histological analysis of a skin biopsy showing typical full-thickness epidermal necrolysis due to extensive keratinocyte apoptosis. Differential diagnosis includes linear IgA dermatosis and paraneoplastic pemphigus, pemphigus vulgaris and bullous pemphigoid, acute generalized exanthematous pustulosis (AGEP), disseminated fixed bullous drug eruption and staphyloccocal scalded skin syndrome (SSSS). Due to the high risk of mortality, management of patients with SJS/TEN requires rapid diagnosis, evaluation of the prognosis using SCORTEN, identification and interruption of the culprit drug, specialized supportive care ideally in an intensive care unit, and consideration of immunomodulating agents such as high-dose intravenous immunoglobulin therapy. SJS and TEN are severe and life-threatening. The average reported mortality rate of SJS is 1-5%, and of TEN is 25-35%; it can be even higher in elderly patients and those with a large surface area of epidermal detachment. More than 50% of patients surviving TEN suffer from long-term sequelae of the disease.

New insights in toxic epidermal necrolysis (Lyell's syndrome): clinical considerations, pathobiology and targeted treatments revisited

Drug-induced toxic epidermal necrolysis (TEN), also known as Lyell's syndrome, is a life-threatening drug reaction characterized by extensive destruction of the epidermis and mucosal epithelia. The eyes are typically involved in TEN. At present, the disease has a high mortality rate. Conceptually, TEN and the Stevens-Johnson syndrome are closely related, although their severity and outcome are different. Distinguishing TEN from severe forms of erythema multiforme relies on consideration of aetiological, clinical and histological characteristics. The current understanding of the pathomechanism of TEN suggests that keratinocytes are key initiator cells. It is probable that the combined deleterious effects on keratinocytes of both the cytokine tumour necrosis factor (TNF)-alpha and oxidative stress induce a combination of apoptotic and necrotic events. As yet, there is no evidence indicating the superiority of monotherapy with corticosteroids, ciclosporin (cyclosporine) or intravenous immunoglobulins over supportive care only for patients with TEN. However, the current theory of TEN pathogenesis supports the administration of a combination of antiapoptotic/antinecrotic drugs (e.g. anti-TNF-alpha antibodies plus N-acetylcysteine) targeting different levels of the keratinocyte failure machinery.

Retrospective analysis of 32 pediatric patients with anticonvulsant hypersensitivity syndrome (ACHSS)

OBJECTIVE

To review 32 pediatric patients with anticonvulsant hypersensitivity syndrome.

DESIGN

Retrospectively, data and photographs were collected on 32 patients who had been diagnosed with anticonvulsant hypersensitivity syndrome.

SETTING

The sections of dermatology at Children's Memorial Hospital in Chicago, Illinois, and Children's Mercy Hospitals and Clinics in Kansas City, Missouri.

MAIN OUTCOME MEASURES

Presentation, implicated medications, laboratory evaluations, complications, treatment and outcome.

RESULTS

The mean age of all patients with anticonvulsant hypersensitivity syndrome (ACHSS) was 8.9 years. The mean duration of anticonvulsant therapy before onset of symptoms was 3 weeks. Phenytoin, carbamazepine, and phenobarbital were the most commonly implicated medications. Lamotrigine, oxcarbamazepine, and primidone were implicated in some of our patients. Fever and rash were seen in all patients, while lymphadenopathy was found in 84.4% of patients. Hematologic abnormalities were seen in 93.8% and hepatic involvement was seen in 90.4% of cases, representing the two most commonly involved systems. Atypical lymphocytosis and eosinophilia was seen in 72% and 56% of patients, respectively. Renal and pulmonary involvement were each seen in 15.6% of cases. Systemic steroids were used in 59.4% of ACHSS patients; 16% of patients received intravenous immunoglobulin. No deaths were reported in our group of pediatric patients.

CONCLUSIONS

The ACHSS is a distinct clinical entity which may occur in pediatric patients treated with anticonvulsants, and may have potentially life-threatening consequences. Involvement of multiple organ systems, including the hematologic, hepatic, renal, and pulmonary systems was common. Treatment varied widely, but ranged from supportive care to systemic corticosteroids.

Skin diseases in intensive care medicine

Though most dermatoses are not life-threatening, skin diseases play an important role in intensive care medicine. Skin findings in intensive care patients may reflect the underlying disease or be complications of intensive medical care. Most important are drug reactions, infections, bacterial toxin reactions, erythroderma, ANCA-positive vasculitides (such as Wegener granulomatosis) and bleeding disorders.

Erythema multiforme and related disorders

Erythema multiforme (EM) and related disorders comprise a group of mucocutaneous disorders characterized by variable degrees of mucosal and cutaneous blistering and ulceration that occasionally can give rise to systemic upset and possibly compromise life. The clinical classification of these disorders has often been variable, thus making definitive diagnosis sometimes difficult. Despite being often caused by, or at least associated with, infection or drug therapy, the pathogenic mechanisms of these disorders remain unclear, and as a consequence, there are no evidence-based, reliably effective therapies. The present article reviews aspects of EM and related disorders of relevance to oral medicine clinical practice and highlights the associated potential etiologic agents, pathogenic mechanisms and therapies.

Toxic epidermal necrolysis

Toxic epidermal necrolysis (TEN) is an unpredictable, life-threatening drug reaction associated with a 30% mortality. Massive keratinocyte apoptosis is the hallmark of TEN. Cytotoxic T lymphocytes appear to be the main effector cells and there is experimental evidence for involvement of both the Fas-Fas ligand and perforin/granzyme pathways. Optimal treatment for these patients remains to be clarified. Discontinuation of the offending drug and prompt referral to a burn unit are generally agreed upon steps. Beyond that, however, considerable controversy exists. Evidence both pro and con exists for the use of IVIG, systemic corticosteroid, and other measures. There is also evidence suggesting that combination therapies may be of value. All the clinical data, however, is anecdotal or based on observational or retrospective studies. Definitive answers are not yet available. Given the rarity of TEN and the large number of patients required for a study to be statistically meaningful, placebo controlled trials are logistically difficult to accomplish. The absence of an animal model further hampers research into this condition. This article reviews recent data concerning clinical presentation, pathogenesis and treatment of TEN.

LEARNING OBJECTIVES

At the conclusion of this learning activity, participants should have acquired a more comprehensive knowledge of our current understanding of the classification, clinical presentation, etiology, pathophysiology, prognosis, and treatment of TEN.

Analytical quantification of the inflammatory cell infiltrate and CD95R expression during treatment of drug-induced toxic epidermal necrolysis

The treatment of drug-induced toxic epidermal necrolysis (TEN) remains unsatisfactory. Intravenous immunoglobulins (IVIg) and intravenous cyclosporin A (CsA) have shown some efficacy in short series of patients. We assessed the effects of IVIg and CsA on TEN lesional and apparently uninvolved skin using standard histology and immunohistochemistry. Cutaneous biopsies were taken from necrotic and clinically uninvolved TEN skin at admission (D1) before any treatment, and after a 5-day treatment (D5). Two IVIg-treated patients (0.75 g/kg/day), two CsA-treated patients (5 mg/kg/day) and two control patients only receiving supportive care were compared. Biopsies were examined by standard histology and immunohistochemistry using antibodies directed to CD68 antigen (macrophages), CD45R0 antigen (activated T lymphocytes), Factor XIIIa (dermal dendrocytes) and the CD95 receptor (apoptosis marker). The different cell densities were evaluated by computerized image analysis. The clinical outcomes with the different treatments were also recorded. There was no obvious difference in the duration of hospitalization in intensive care unit between the three groups but one patient passed away in each of the IVIg- and CsA-groups. At D5, no differences were found between the three groups in the histological and clinical rate of re-epithelialization, and in the evolution of T lymphocyte, macrophage and dendrocyte densities in the epidermis and dermis. However, the expression of the CD95 receptor was similarly and strongly abated at D5 in the epidermis of IVIg- and CsA-treated patients, while it was conversely increased in the two patients under supportive care only. Such a difference was found both in necrotic and uninvolved sites. IVIg and CsA treatments thus appeared to exert no obvious effect on the inflammatory infiltrate, but both abated the expression of the CD95 receptor in the skin of TEN patients. This effect did not seem sufficient to fully reverse the clinical evolution of the disease. It is inferred that IVIg and CsA do not completely abate the TEN process.

Intravenous immunoglobulins and plasmapheresis combined treatment in patients with severe toxic epidermal necrolysis: preliminary report

Toxic epidermal necrolysis (TEN) is an acute drug-induced life-threatening disorder characterised by extensive epidermal exfoliation and high rate of mortality. Between October 2000 and April 2003, five severe TEN patients were evaluated using a specific TEN severity-of-illness scale (SCORTEN) and treated for the first time, with a combined therapy using Intravenous Human Immunoglobulins (IVIG) and plasmapheresis. The standardised mortality ratio (SMR) analysis ([Sigma observed deaths/Sigma expected deaths]x100) was applied to establish how IVIG and plasmapheresis treatment could reduce TEN patient mortality. The observed mortality was one out of five patients corresponding to 20%. The expected mortality based on SCORTEN was 3.319 corresponding to 66%. The SMR analysis revealed a 70% reduction in mortality (SMR=0.30; 95% confidence interval, 0.0-0.96). Our series show a low mortality rate (20%) related to the severity of the patients (66% expected mortality). The use of IVIG in association with plasmapheresis has a rational basis and may be effective in severe TEN patients.

The Use of Systemic Immune Moderators in Dermatology: An Update

In addition to corticosteroids, dermatologists have access to an array of immunomodulatory therapies. Azathioprine, cyclophosphamide, methotrexate, cyclosporine, and mycophenolate mofetil are the systemic immunosuppressive agents most commonly used by dermatologists. In addition, new developments in biotechnology have spurred the development of immunobiologic agents that are able to target the immunologic process of many inflammatory disorders at specific points along the inflammatory cascade. Alefacept, efalizumab, etanercept, and infliximab are the immunobiologic agents that are currently the most well known and most commonly used by dermatologists. This article reviews the pharmacology, mechanism of action, side effects, and clinical applications of these therapies.

Novel Treatments for Drug-Induced Toxic Epidermal Necrolysis (Lyell’s Syndrome)

Drug-induced toxic epidermal necrolysis (TEN) is a life-threatening disease characterized by extensive destruction of the epidermis. It apparently results from the formation of specific toxic drug metabolites by the keratinocytes. The mortality rate which averages 25-30% is mainly due to secondary septicemia, and to ionic and metabolic disturbances following loss of epidermal integrity. Apoptosis is the likely mechanism leading to massive keratinocyte death in TEN. Dysregulations in the tumor necrosis factor-alpha (TNF-alpha) pathway, CD95 system (Fas ligand, CD95L; Fas receptor, CD95R) and calcium homeostasis in the epidermis are involved in this apoptotic process. An active role has also been ascribed to T lymphocytes, macrophages and factor XIIIa-positive dermal dendrocytes. Despite progress, treatment of TEN remains controversial. In the past, systemic glucocorticoids were used in order to target the inflammatory reaction in TEN. However, there was no evidence for improvement of the healing process, while corticosteroids worsened the prognosis by increasing the risk of septicemia. Only a few cases have been treated with other drugs including cyclophosphamide, pentoxyfilline, thalidomide, anti-TNF-alpha antibodies and cyclosporin A. In the recent past, some TEN patients were treated with intravenous human immunoglobulins (IVIG). The rationale for such a treatment was to block the CD95 system on keratinocytes. The early promising clinical results of IVIG treatment in TEN were subsequently challenged. This review compares the effectiveness and drawbacks of the major drugs presently used in TEN treatment. Some future prospects in TEN management are also discussed.

Assessment and management of cutaneous reactions with amifostine administration: Findings of the ethyol (amifostine) cutaneous treatment advisory panel (ECTAP)

PURPOSE

To review reports of severe skin reactions during amifostine treatment.

METHODS AND MATERIAL

The expert panel reviewed postmarketing reports of skin reactions and discussed strategies for evaluation and management.

RESULTS

Between 1994 and April 2002, 35 events were classified as severe skin reactions worldwide: erythema multiforme (8), Stevens-Johnson syndrome (10), toxic epidermal necrolysis (11), toxicoderma (3), and bullae (3). Unadjusted incidences were 6-9 per 10,000 radiotherapy patients and 0.8-1 per 10,000 chemotherapy patients. In 10 patients (29%) amifostine was continued after cutaneous signs and symptoms appeared.

CONCLUSIONS

Practical recommendations for practicing clinicians were developed. Cutaneous evaluation for rash, ulceration, or lesions-particularly on lips/mucosa, palmar/plantar surfaces, and the trunk-should be performed before amifostine administration. Reactions can be classified as local injection site/radiation port reactions or non-injection site reactions; and non-injection site reactions with associated fever or constitutional symptoms must be differentiated from radiation-induced dermatitis or cutaneous reaction with another etiology. Amifostine should be permanently discontinued for severe skin reactions or reactions associated with constitutional symptoms not known to be due to any other etiology. Increased physician awareness, proper patient management, monitoring before administration, and early intervention/discontinuation for non-injection site reactions may reduce the incidence of cutaneous reactions and enhance amifostine safety.

Antimetabolites and cytotoxic drugs

Mycophenolic mofetil, azathioprine, thioguanine, methotrexate, and cyclophosphamide were initially used for the treatment of malignancies. Because of their immunosuppressive activity, the range of diseases responsive to these medications has expanded to include various autoimmune-related diseases. Discussion includes a historical perspective of each medication, recent updates on responsive dermatologic conditions, dosages, monitoring guidelines, and medication expense.

Drug-induced Stevens-Johnson syndrome/toxic epidermal necrolysis

Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) is a rare (occurring in approximately 2 to 3 people/million population/year in Europe and the US), life-threatening, intolerance reaction of the skin. It is most often caused by drugs (most commonly sulfonamides, nonsteroidal anti-inflammatory drugs, antimalarials, anticonvulsants, and allopurinol). SJS/TEN is characterized by a macular exanthema ('atypical targets') which focusses on the face, neck, and the central trunk regions. Lesions show rapid confluence, a positive Nikolsky's sign, and quickly result in widespread detachment of the epidermis and erosions. Mucosal, conjunctival, and anogenital mucous membranes are prominently involved. Histopathology shows satellite cell necrosis in the early stages progressing to full thickness necrosis of the epidermis, contrasting with rather inconspicuous inflammatory infiltrates of the dermis. Damage to the skin is thought to be mediated by cytotoxic T lymphocytes and mononuclear cells which induce apoptosis in keratinocytes expressing drug-derived antigens at their surfaces. No guidelines for the treatment of SJS/TEN exist since no controlled clinical trials have ever been performed. The controversy over whether systemic corticosteroids should be used to curtail progression is still unresolved; while many authors agree that corticosteroids do in fact suppress progression, it is obvious that they also greatly enhance the risk of infection, the complication which most frequently leads to a fatal outcome. It appears reasonable to only administer corticosteroids in the phase of progression and to withdraw them as soon as possible, and to add antibacterials for prophylaxis. Recently, in a small series of patients, intravenous immunoglobulins were presumed to be effective by the blockade of lytic Fas ligand-mediated apoptosis in SJS/TEN. However, these results have to be confirmed by large clinical trials. Supportive treatment and monitoring of vital functions is of utmost importance in SJS/TEN, and out-patient treatment is unacceptable. Recovery is usually slow, depending on the extent and severity and the presence of complications, and may take 3 to 6 weeks. Skin lesions heal without scars as a rule, but scarring of mucosal sites is a frequent late complication, potentially leading to blindness, obliteration of the fornices and anogenital strictures. There is no reliable laboratory test to determine the offending drug; diagnosis rests on the patient's history and the empirical risk of drugs to elicit skin SJS/TEN. Provocation tests are not indicated since re-exposure is likely to elicit a new episode of SJS/TEN of increased severity.

Pulse intravenous cyclophosphamide therapy for dermatologic disorders

Cyclophosphamide is a potent immunosuppressive agent that has an important role in the treatment of autoimmune, neoplastic, granulomatous, and neutrophilic disorders. Pulse intravenous cyclophosphamide has been shown to be efficacious for several dermatologic disorders, particularly pemphigus vulgaris, with a low incidence of toxicity reported. As reported earlier, studies performed on the use of pulse intravenous cyclophosphamide in the treatment of a variety of dermatology-related diseases strongly suggest that the toxicities frequently noted with the use of oral cyclophosphamide therapy may be significantly less common with pulse intravenous administration of cyclophosphamide. The short follow-up period of patients treated with this modality so far, however, requires constant vigilance for the development of side effects, particularly secondary malignancy. At this time, pulse intravenous cyclophosphamide is a promising treatment modality with an acceptable risk profile for moderate-to-severe dermatologic diseases recalcitrant to standard therapy. Prospective comparative trials are needed to assess further the efficacy and toxicity of this therapy.

Treatment of severe drug eruptions

Severe drug eruptions are rare, life-threatening events. The management begins with the withdrawal of the suspect drug(s). We recently confirmed that an earlier withdrawal of drugs with short elimination half-life was associated with a better survival of patients with Stevens-Johnson syndrome (SJS) or toxic epidermal necrolysis (TEN). In cases of "acute skin failure" (exfoliative dermatitis, extensive SJS or TEN), management of patients must be undertaken in specialized intensive care units or in burn units. The main principles of symptomatic therapy are the same as for major burns: warming of the environment, correction of electrolyte disturbances, high caloric intake, and prevention of sepsis. The suspected immunologic orgin of drug eruptions prompted the use of corticosteroids, immunosuppressive drugs, and anti-cytokines. Systemic corticosteroids are useful in "hypersensitivity syndrome" when visceral lesions depend on infiltration by activated cosinophils. Systemic corticosteroids were shown to be deleterious in cases of advanced TEN. Their potential usefulness at earlier stages of SJS or TEN remains controversial. High intravenous doses of cyclophosphamide or oral cyclosporin have been administered to a few patients with TEN, most often following ineffective treatment with corticosteroids for 1 to 5 days. It remains doubtful that the progression of the lesions was shortened. A few patients appeared to benefit from treatment with pentoxifyllin, a drug suppressing the production of TNF. Thalidomide, another suppressor of TNF production, significantly increased the death rate when tested in a double-blind placebo controlled trial in patients with early TEN. High dose intravenous immunoglobulins were used in 10 patients with TEN on the basis of their ability to inhibit fas-fas ligand mediated apoptosis. The potential benefit of this treatment needs confirmation by further studies. Patients and their first degree relatives should be advised to avoid the responsible drug and chemically related compounds. Regulatory agencies should be notified of such cases.

Immunosuppressive agents in dermatology. An update

Azathioprine, cyclophosphamide, methotrexate, and cyclosporine are the immunosuppressive agents most commonly used by dermatologists. Azathioprine has a relatively good safety profile and is therefore often preferred for the treatment of chronic eczematous dermatitides and bullous disorders. Awareness of the role of genetic polymorphisms in its metabolism can increase the efficacy and safety of this drug. Cyclophosphamide is an antimetabolite that has a more rapid onset of immunosuppressive effect than azathioprine, but has significant short-term and long-term toxicity. It is of use in fulminant, life-threatening cutaneous disease. Methotrexate is an antimetabolite that has significant anti-inflammatory activity. Despite its hepatotoxicity, its role in inflammatory dermatoses is broadening. Likewise, the role of cyclosporine is being expanded. This drug has potent T-cell inhibitory effects secondary to interference with intracellular signal transduction. Given the evidence for cumulative renal toxicity, it currently has a role in the short-term treatment of refractory psoriasis and atopic dermatitis, as well as in select inflammatory dermatoses. Familiarity with disease-specific clinical efficacy, side-effect profile, and dosage allows the successful and judicious use of these drugs in dermatologic disorders.